All categories

2 years ago

"In analyzing distances by apply ing the physics of gravitational forces, an astronomer has obtained the expression

Physics

1 answer:

zavuch27 [327]2 years ago

6 0

Answer:

The value of R is $1.72\times10^{11}\ m$ .

(B) is correct option.

Explanation:

Given that,

In analyzing distances by apply ing the physics of gravitational forces, an astronomer has obtained the expression

$R=\sqrt{\dfrac{1}{(\dfrac{1}{140\times10^{9}})^2-(\dfrac{1}{208\times10^{9}})^2}}$

We need to calculate this for value of R

$R=\sqrt{\dfrac{1}{(\dfrac{1}{140\times10^{9}})^2-(\dfrac{1}{208\times10^{9}})^2}}$

$R=1.89\times10^{11}\ m$

So, The nearest option of the value of R is $1.72\times10^{11}\ m$

Hence, The value of R is $1.72\times10^{11}\ m$ .

You might be interested in

An experiment is designed to test what color of light will activate a photoelectric cell the best. The photocell is set in a cir

Natalija [7]

A photoelectric cell is an electronic device which is used to convert light energy into electric energy.The operation of this device is based on photoelectric effect.

Light of suitable frequency i.e greater or equal to threshold frequency will fall on the cathode maintained at negative potential.The electron emission will take place and these electrons are drifted towards the anode which is at positive potential.

Here,only those radiations will be capable of emitting electrons irrespective of surface barrier of metals whose energy is greater than the work function.

We know that the radiation having long wavelength has least energy as energy and wavelength are inversely proportional to each other.

$Mathematically\ energy\ E=\frac{hc}{\lambda}$

Here h is the Planck's constant,c is the velocity of light.

Here we have been given red light and blue light.

In the visible spectrum of radiation, the red light has longer wavelength than all other colors of light.Hence blue light has more energy as it's wavelength is less as compared to red light.

Hence, the blue light will activate the most and red the least.

3 0

1 year ago

Read 2 more answers

Compute the mean and maximum velocities for a liquid with a flow rate of 20 L/min in a 1.5-in nominal diameter sanitary pipeline

vlada-n [284]

Answer:

Mean velocity = 0.292 m/s

Maximum velocity = 0.584 m/s

The flow is laminar as Re = 229.2

Explanation:

D = 1.5 inches = 0.0381 m

Q = volumetric flow rate = 20 L/min = 0.000333 m³/s

Q = A × v

A = Cross sectional Area = πD²/4 = π(0.0381)²/4 = 0.00114 m²

v = average velocity

v = Q/A = 0.000333/0.00114 = 0.292 m/s

For flow in circular pipes, maximum velocity = 2 × average velocity = 2 × 0.292 = 0.584 m/s

To check if the flow is laminar or turbulent, we need its Reynolds number

Re = (ρvD)/μ

ρ = 1030 kg/m

v = 0.292 m/s

D = 1.5 inches = 0.0381 m

μ = 50 cP = 0.5 poise = 0.05 Pa.s

Re = (1030 × 0.292 × 0.0381)/0.05 = 229.2

For laminar flow, Re < 2100

For turbulent flow, Re > 4000

And 229.2 < 2100, hence, this flow is laminar.

7 0

2 years ago

Energy conservation with conservative forces: Two identical balls are thrown directly upward, ball A at speed v and ball B at sp

MatroZZZ [7]

Answer:

E) True. Ball B will go four times as high as ball A because it had four times the initial kinetic energ

Explanation:

To answer the final statements, let's pose the solution of the exercise

Energy is conserved

Initial

Em₀ = K

Em₀ = ½ m v²

Final

Emf = U = mg h

Em₀ = emf

½ m v² = mgh

h = v² / 2g

For ball A

h_A = v² / 2g

For ball B

h_B = (2v)² / 2g

h_B = 4 (v² / 2g) = 4 h_A

Let's review the claims

A) False. The neck acceleration is zero, it has the value of the acceleration of gravity

B) False. Ball B goes higher

C) False has 4 times the gravitational potential energy than ball A

D) False. It goes 4 times higher

E) True.

6 0

1 year ago

You have been abducted by aliens and find yourself on a strange planet. Fortunately, you have a meter stick with you. You observ

defon

Answer:

$36.4276\ m/s^2$

Explanation:

m = Mass of stick

L = Length of stick = 1 m

h = Center of mass of stick = $\dfrac{1}{2}=0.5\ m$

g = Acceleration due to gravity

T = Time period = 0.85 s

Time period is given by

$T=2\pi\sqrt{\dfrac{I}{mgh}}$

Moment of inertia is given by

$I=m\dfrac{L^2}{3}$

$T=2\pi\sqrt{\dfrac{m\dfrac{L^2}{3}}{mgh}}\\\Rightarrow T=2\pi\sqrt{\dfrac{L^2}{3gh}}\\\Rightarrow g=\dfrac{4\pi^2L^2}{3hT^2}\\\Rightarrow g=\dfrac{4\pi^2\times 1^2}{3\times 0.5\times 0.85^2}\\\Rightarrow g=36.4276\ m/s^2$

The acceleration of gravity on this planet is $36.4276\ m/s^2$

0 0

1 year ago

Read 2 more answers

An 1876 N crate is being pushed across a level force at a constant speed by a force of 747 N. What is the coefficient of kinetic

nekit [7.7K]

The crate only moves horizontally, so its net vertical force is 0. The only forces acting in the vertical direction are the crate's weight (pointing downward) and the normal force of the surface on the crate (pointing upward). By Newton's second law, we have

∑ F (vertical) = n - mg = 0 → n = mg = 1876 N

where n is the magnitude of the normal force.

In the horizontal direction, the crate is moving at a constant speed and thus with no acceleration, so it's completely in equilibrium and the net horizontal force is also 0. The only forces acting on it in this direction are the 747 N push (pointing in the direction of the crate's motion) and the kinetic friction opposing it (pointing in the opposite direction). By Newton's second law,

∑ F (horizontal) = 747 N - f = 0 → f = 747 N

The frictional force is proportional to the normal force by a factor of the coefficient of kinetic friction, µ, such that

f = µn → µ = f / n = (747 N) / (1876 N) ≈ 0.398188 ≈ 0.40

8 0

2 years ago